98 citations · 1.2k across the 60 of their papers we have counts for
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Wide binaries without viable bound Newtonian orbits
L. Pasquini, R. Saglia, F. Patat +7
Context. Wide binaries offer a unique opportunity to test gravity in the low acceleration regime, where deviations from Newtonian dynamics may appear. Aims. We use high-resolution…
A portrait of the rotation of Ultra-Cool Dwarfs revealed by TESS
D. O. Fontinele, P. D. S. de Lima, Y. S. Messias +7
This study presents the results of a search for rotation signature in 250 Gaia DR3 Ultra-Cool Dwarfs (UCDs) with TESS light curves. We identified 71 targets with unambiguous period…
Pulsation in TESS Objects of Interest
R. L. Gomes, B. L. Canto Martins, D. O. Fontinele +11
We report the discovery of three Transiting Exoplanet Survey Satellite Objects of Interest (TOI) with signatures of pulsation, observed in more than one sector. Our main goal is to…
Accurate mass-radius ratios for Hyades white dwarfs
L. Pasquini, A. F. Pala, M. Salaris +4
We use the ESPRESSO spectrograph at the Very Large Telescope to measure velocity shifts and gravitational redshifts of eight bona fide Hyades white dwarfs, with an accuracy better…
Rotation signature of TESS B-type stars. A comprehensive analysis
L. F. Barraza, R. L. Gomes, Y. S. Messias +11
Stellar rotation is a fundamental observable that drives different aspects of stellar and planetary evolution. In this work, we present an unprecedented manifold analysis of 160 B-…
A search for rotation periods in 1000 TESS objects of interest
Bruno L. Canto Martins, Roseane L. Gomes, Yuri S. Messias +8
The high quality light curves from the Transiting Exoplanet Survey Satellite (TESS) represent a unique laboratory for the study of stellar rotation, a fundamental observable drivin…
New Suns in the Cosmos V: Stellar rotation and multifractality in active \textit{Kepler} stars
D. B. de Freitas, M. M. F. Nepomuceno, L. D. Alves Rios +2
In the present study, high-precision time series photometry for the active \emph{Kepler} stars is described in the language of multifractals. We explore the potential of using the…
New Suns in the Cosmos IV: the multifractal nature of stellar magnetic activity in \textit{Kepler} cool stars
D. B. de Freitas, M. M. F. Nepomuceno, M. Gomes de Souza +5
In the present study, we investigate the multifractal nature of a long-cadence time series observed by the \textit{Kepler} mission for a sample of 34 M dwarf stars and the Sun in i…
On the incidence of \textit{WISE} infrared excess among solar analog, twin and sibling stars
Antônio D. Costa, Bruno L. Canto Martins, Izan C. Leão +4
This study presents a search for IR excess in the 3.4, 4.6, 12 and 22 m bands in a sample of 216 targets, composed of solar sibling, twin and analog stars observed by the \texti…
New Suns in the Cosmos III: multifractal signature analysis
D. B. de Freitas, M. M. F. Nepomuceno, P. R. V. de Moraes Junior +7
In present paper, we investigate the multifractality signatures in hourly time series extracted from CoRoT spacecraft database. Our analysis is intended to highlight the possibilit…
Rotation period distribution of CoRoT and Kepler Sun-like stars
I. C. Leão, L. Pasquini, C. E. Ferreira Lopes +9
We study the distribution of the photometric rotation period (Prot), which is a direct measurement of the surface rotation at active latitudes, for three subsamples of Sun-like sta…
Stellar Cycles from Photometric Data: CoRoT Stars
C. E. Ferreira Lopes, I. C. Leão, D. B. de Freitas +3
Until a few years ago, the amplitude variation in the photometric data had been limitedly explored mainly because of time resolution and photometric sensitivity limitations. This i…
The variability behavior of CoRoT M-giant Stars
C. E. Ferreira Lopes, V. Neves, I. C. Leão +8
For 6 years the Convection, Rotation, and Planetary Transits (CoRoT) space mission has acquired photometric data from more than one hundred thousand point sources towards and direc…
Stellar parameters for stars of the CoRoT exoplanet field
C. Cortés, S. C. Maciel, S. Vieira +7
Aims:To support the computation and evolutionary interpretation of periods associated with the rotational modulation, oscillations, and variability of stars located in the CoRoT fi…
The rotational behavior of Kepler Stars with Planets
F. Paz-Chinchón, I. C. Leão, J. P. Bravo +6
We analyzed the host stars of the present sample of confirmed planets detected by Kepler and Kepler Objects of Interest (KOI) to compute new photometric rotation periods and to stu…
The WFCAM Multi-wavelength Variable Star Catalog
C. E. Ferreira Lopes, I. Dékány, M. Catelan +4
Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for the time-do…
A catalog of rotational and radial velocities for evolved stars V. Southern stars
J. R. De Medeiros, S. Alves, S. Udry +3
Rotational and radial velocities have been measured for 1589 evolved stars of spectral types F, G and K and luminosity classes IV, III, II and Ib, based on observations carried out…
New Suns in the Cosmos?
D. B. de Freitas, I. C. Leão, C. E. F. Lopes +5
The present work reports on the discovery of three stars that we have identified to be rotating Sun-like stars, based on rotational modulation signatures inferred from light curves…
Overview of semi-sinusoidal stellar variability with the CoRoT satellite
J. R. De Medeiros, C. E. Ferreira Lopes, I. C. Leao +13
To date, the CoRoT space mission has produced more than 124,471 light curves. Classifying these curves in terms of unambiguous variability behavior is mandatory for obtaining an un…
A nonextensive approach to the stellar rotational evolution I. F and G type stars
D. B. de Freitas, J. R. De Medeiros
The pioneering study by Skumanich (1972) showed that the rotational velocity of G-type Main-Sequence (MS) stars decreases with stellar age according to $t^{-…
Fundamental properties of nearby stars and the consequences on DeltaY/DeltaZ
Aldo A. R. Valcarce, Márcio Catelan, José R. De Medeiros
One of the greatest difficulties in astrophysics is the determination of the fundamental stellar parameters (FSPs), one of which is the initial mass fraction of helium (Y). However…
Nonextensivity in the Solar Neighborhood
D. B. de Freitas, J. R. De Medeiros
In the present study, we analyze the radial velocity distribution as a function of different stellar parameters such as stellar age, mass, rotational velocity and distance to the S…
Lithium abundances and extra mixing processes in evolved stars of M67
B. L. Canto Martins, A. Lèbre, A. Palacios +5
Aims. We present a spectroscopic analysis of a sample of evolved stars in M67 (turn-off, subgiant and giant stars) in order to bring observational constraints to evolutionary model…
Solar twins in M67 : Evolutionary status and lithium abundance
M. Castro, J. D. do Nascimento, K. Biazzo +2
We determine the age and mass of the three best solar twin candidates in open cluster M67 through lithium evolutionary models. We computed a grid of evolutionary models with non-st…